Device and method for preventing growth of bacteria or removing bacteria in duct of dental unit

ABSTRACT

A device ( 1 ) for preventing the growth of the bacteria or removing the bacteria bred on the inner wall surfaces of the ducts ( 8, 9, 10 ) of a dental unit, comprising a transponder ( 3 ) having a control unit ( 2 ) generating electric signals including audible frequency components, a coil ( 3   a ), and a case ( 3   b ) for storing the coil ( 3   a ) and mounting means ( 5 ) for mounting the transponder ( 3 ) on the outer wall surface of the duct ( 8 ), whereby an audible frequency electric signal allowed to transmit through the ducts ( 8, 9, 10 ) is generated by applying the electric signals to the coil ( 3   a ).

TECHNICAL FIELD

The present invention in this application relates to an apparatus andmethod for preventing growth of microbia propagating themselves on aninternal wall of a waterline of a dental unit or for removing themicrobia.

BACKGROUND ART

In a dental clinic, a dental unit in which various treatment instrumentsand treatment goods are arranged around a dental chair is installed. Thedental unit includes, as treatment instruments using water, a handpiecefor grinding a tooth (tooth grinding tool), a scaler for removing tartar(tartar removing tool), a syringe for cleaning a mouth (mouth cleaningtool), and the like to which service water is supplied.

In the case where the dental unit is installed in a room of a building,a connection box for relay in the dental unit, a tap of a washstand, andthe like are connected to a waterline which is branched from a main pipefor receiving supply of service water chlorinated in accordance with apredetermined environmental sanitation standard and which is led intothe room.

To the connection box, an airline from a compressor for dischargingcompressed air is usually also connected. The airline and the waterlineare connected to a control center via the unit body.

To the control center, a plurality of tubes whose tips are provided withthe handpiece, the syringe, and a vacuum cleaner for discharging waterare connected, and a lead wire from a foot switch and the like is alsoconnected.

When any of the switches of the instruments is turned on at the time oftreatment, the control center transmits high-pressure water to thehandpiece side via the tube and the high-pressure water rotates aturbine cutter attached to the head of the handpiece, thereby enablinggrinding of a tooth. The control center also supplies low-pressure waterto the syringe via the tube so that the water is injected into themouth. In such a manner, tooth treatment can be performed by usingservice water.

In the waterline connected to the dental unit, differently from ageneral water pipe, microbia and bacteria easily propagate themselves.It is feared that the water used for treatment of teeth is bad for thehealth of the patient.

Specifically, each of the waterlines to the handpiece, syringe, scaler,a water supplier for rinsing out the mouth, and the like from whichwater is supplied directly to the mouth of a patient is branched in somemidpoint and its diameter decreases toward the end side. On the side ofthe treatment instruments connected to the waterlines, water is notalways used. Therefore, retention time of the water in the waterlinestends to be long.

In dental clinics, the room temperature is maintained almost constant inall seasons. Consequently, even when the temperature of service watersent to the main pipe side is low, the water temperature in thewaterlines rises by being influenced by the higher room temperature ofthe dental clinics. The environment of the internal wall face of thewaterline is suitable for culturing microbia.

Consequently, even when the number of colonies of microbia and bacteriaincluded in one milliliter of chlorinated service water is a few on themain pipe side as the source of water, it sharply increases on thewaterline side of the dental unit in which the temperature is about roomtemperature. There is a case that the number of colonies increased toseveral hundreds of thousands on the end side of each of the waterlinesattached to the various treatment instruments.

As described above, when microbia and bacteria increased in thewaterline enter the body through the mouth of a patient at the time oftreatment, they may cause various diseases and, what is more, a problemof hospital infection arises. Consequently, it has been expected thateffective means for sterilizing water in a waterline used in a dentalclinic, a dental department in a hospital, and the like is developed.

An object of the invention is to provide an apparatus and method forpreventing growth of microbia and bacteria on an internal wall of awaterline of a dental unit or for removing them, thereby enabling aproblem that the patient is infected in a clinic or hospital to beavoided.

DISCLOSURE OF THE INVENTION

To solve the problems, according to the present invention, there isprovided an apparatus for preventing growth of microbia propagatingthemselves on an internal wall of a waterline of a dental unit or forremoving the microbia, comprising:

electric signal generating means for generating an electric signalincluding an audio frequency component; a transponder including a coiland a case for housing the coil; and means for attaching the transponderto an external wall of the waterline, wherein the electric signal isapplied to the coil so that an audio electronic signal to be sentthrough the waterline can be generated.

And according to the invention, there is provided a method forpreventing growth of microbia propagating themselves on an internal wallof a waterline of a dental unit or for removing the microbia, comprisingthe steps of:

generating an electric signal including an audio frequency component;attaching a transponder including a coil and a case for housing the coilto an external wall of the waterline; and applying the electric signalto the coil, thereby generating an audio electronic signal to be sentthrough the waterline.

According to the apparatus and method, growth of microbia can beprevented by the audio electronic signal. The audio electronic signal issent through a waterline so that an effect of prevention of the growthof the microbia can be obtained within a wide range of the waterline.

In particular, if the electric signal frequency-modulates around apredetermined frequency and the frequency modulation causes the audioelectronic signal to include a harmonics component, the effect becomesmore conspicuous.

Preferably, the predetermined frequency is between 1500 Hz and 2500 Hz.

When a face of the transponder which comes in contact with the waterlinehas a concave shape whose section is circular, an attaching state of atransponder to a waterline can be stabilized.

It is preferable that the transponder is attached near an end of thewaterline.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing an external appearance of an apparatusaccording to an embodiment of the present invention;

FIG. 2 is a schematic block diagram showing the apparatus according tothe embodiment of the present invention;

FIG. 3( a) is a side view showing, in detail, a shape of a transponderand the like, FIG. 3( b) is a transverse sectional view showing, indetail, the shape of the transponder and the like, and FIG. 3( c) is aview showing a state in which the transponder is attached to awaterline; and

FIG. 4 is a view showing a state of use in which the apparatus accordingto the present invention is attached to a dental unit.

BEST MODE FOR CARRYING OUT THE INVENTION

Representative microbia growing in a waterline are psuedomonas,klebsiella, legionella, mycobacterium, mesophilic, heterotrophic, andmoraxella.

In this specification, microbia include bacteria and yeast. The presentinvention is mainly effective at preventing microbia from growing in awaterline or removing the microbia in the waterline.

An embodiment of the present invention will be described below withreference to the drawings.

FIG. 1 is a view showing an external appearance of an apparatusaccording to an embodiment of the present invention, and FIG. 2 is aschematic block diagram showing the apparatus.

In FIG. 1, the reference numeral 1 denotes the apparatus according tothe embodiment of the present invention, the reference numeral 2 denotesa control unit, the reference numeral 3 denotes a transponder, and thereference numeral 4 denotes a coaxial cable.

The control unit 2 acting as electric signal generating means has avoltage capacitor oscillator 2 a provided therein. The voltage capacitoroscillator 2 a is a main part for generating an electric signal, andserves to generate an electric signal which fluctuates in a range of2000 Hz±40 Hz.

In other words, the electric signal frequency-modulates in a range of1960 Hz to 2040 Hz. A center frequency is not always 2000 Hz but anyaudio frequency can be used. In particular, it is preferable that aspecific frequency between 1500 Hz and 2500 Hz should be set to thecenter frequency.

Power is supplied from the outside to the control unit 2 by means of anelectric power unit (not shown).

The transponder 3 mainly includes a coil 3 a and a case 3 b for housingthe coil 3 a. The coil 3 a is formed by winding a filament-shaped copperwire around a coil former about 88 times. The coil former has a ferritecore. The coil 3 a has a reactance of 36 microhenry.

The control unit 2 and the transponder 3 are connected through thecoaxial cable 4. The electric signal output from the control unit 2 issent to the coil 3 a of the transponder 3 through the coaxial cable 4.

FIG. 3( a) is a side view showing, in detail, a shape of the transponder3 and the like, FIG. 3( b) is a transverse sectional view showing thesame, and FIG. 3( c) is a view showing a state in which the transponder3 is attached to a waterline.

The transponder 3 has an almost cylindrical shape. A sectional shape ofthe transponder 3 has a concave portion 3 d formed like a circular arcas shown in FIG. 3( b). The concave portion 3 d is formed to stabilizethe state of attachment to the waterline 8 when the transponder 3 isattached to the waterline 8 of the dental unit 11 and the like (see FIG.4).

Two trenches 3 c are formed on sides of the transponder 3 in acircumferential direction. The trenches 3 c are formed in order to fitbind members 5 therein when the transponder 3 is to be attached to thewaterline 8 by means of the bind members 5.

FIG. 4 is a use state diagram showing a state where the apparatus 1 isattached to the waterline 8 of the dental unit 11.

In FIG. 4, the reference numeral 6 denotes the floor of a room of adental clinic in a building. On the floor 6, the dental unit 11 and awashstand 19 are mounted, and a main pipe 7 to which service water issupplied is extended under the floor in a hidden state.

The reference numeral 8 denotes a waterline as the transmission sourceof water connected to the main pipe 7. From the water line 8, a waterline 9 and a water line 10 each having a diameter smaller than that ofthe water line 8 are branched. To the end of the waterline 9, a tap 20provided for the washstand 19 is connected. To the end of the waterline10, a connection box 13 is connected. To each of them, service waterfrom the main pipe 7 side is sent.

The reference numeral 11 denotes the dental unit. In a seating 12 a of adental chair 12, the connection box 13 is provided. A unit body 14 isdisposed on one side of the dental chair 12.

To the connection box 13, an airline (not shown in FIG. 4) from acompressor for discharging compressed air is connected. To theconnection box 13, an electric scaler for removing tartar and a mouthrinse water supplier for supplying water used to rinse the mouth areconnected via waterlines each having a small diameter.

To the unit body 14, a waterline 10 a and an airline disposed so as tobe hidden from the connection box 13 side are connected. An exposedwaterline 10 b is extended from the unit body 14 and is connected to thecontrol center 15 side. The waterline 10 b is connected to the waterline10 a. The reference numeral 18 denotes an illuminating lamp attached tothe unit body 14.

To the control center 15, tubular waterlines 10 c and 10 d areconnected. A hand piece 16 for grinding a tooth is attached to the endof the waterline 10 c and a syringe 17 for washing the mouth is attachedto the end of the waterline 10 d.

To the control center 15, a tube (not shown in FIG. 4) to which a vacuumcleaner for discharging water is attached, a foot switch and otheroperation switches as operation parts, and a lead wire from a relayswitch or the like are also connected.

By operating the operation parts (not shown), the control center 15constructed as described above receives service water from the waterline10 b and high-pressure air from the airline, and sends high-pressurewater to the handpiece 16 side via the waterline 10 c. It makes theturbine cutter of the head of the handpiece 16 rotate at high speed. Byoperating the operation parts, low-pressure water is sent to the syringe17 side via the waterline 10 d, so that service water can be suppliedinto the mouth. In such a manner, treatment of teeth can be performed.

As shown in FIG. 4, the transponder 3 is attached to the waterline 8connected to the main pipe 7. The reason why the transponder 3 isattached in this position is because service water flows from the mainpipe 7 to the dental unit 11 and the washstand 19 side via thewaterlines 8, 9, and 10, and an audio electronic signal which will bedescribed later propagates by using, as electric conductor, the servicewater flowing toward the waterlines 10 a to 10 d and the like of thedental unit 11.

The transponder 3 is firmly attached to the waterline 8 by allowing aconcave portion 3 d of the transponder 3 to come in contact with theexternal wall of the waterline 8 and, after that, binding thetransponder 3 and the waterline 8 in a state where the two bind members5 are fit in the trenches 3 c.

The coaxial cable 4 whose one end is connected to the control unit 2 isinserted in a through hole 6 a opened in the floor 6, and the other endof the coaxial cable 4 is connected to the transponder 3.

In such a manner, the transponder 3 can be easily attached to thewaterline 8 without taking the waterline 8 as the transmission source ofwater for coupling the main pipe 7 and the waterlines 9 and 10 from themain pipe 7.

As described above, the electric signal is sent from the control unit 2to the coil 3 a in the transponder 3.

Consequently, the transponder 3 generates, in the waterline 8, an audioelectronic signal which frequency-modulates in a range of 2000 Hz±40 Hz.Harmonics are also generated on the audio electronic signal by thefrequency modulation.

In other words, the audio electronic signal includes a frequencycomponent which fluctuates around 2000 Hz, and a harmonics component.The harmonics can make effects of the present invention (effects ofprevention of growth of microbia and removal of the microbia) moreremarkable.

Such an audio electronic signal is sent through the waterlines 8,9,10.The transponder 3 is in contact with the waterline 8 in the concaveportion 3 d. Consequently, the audio electronic signal is easilygenerated in the waterline 8. Ideally, the audio electronic signal sentthrough the waterlines 8,9,10 has a voltage level of 200 to 600millivolts.

The audio electronic signal is sent over a whole length of thewaterlines 8,9,10,10 a–10 d. The waterlines 8–10 d and the water actingas a medium filled in the waterlines 8–10 d function as conductors forsending the audio electronic signal.

The audio electronic signal breaks off an electrochemical adhesionfunction of individual cells of the microbia, thereby preventing growthof a biofilm of the microbia. Consequently, the microbia cannot adhereto an internal wall of the waterline 8–10 d well. Thus, the cells cannotbe increased.

As described above, the problem of the conventional technique thatservice water retained in a waterline is warmed at room temperature andthe number of colonies of microbia and bacteria included in onemilliliter of service water sharply increases to several hundreds ofthousands toward the end is solved.

Therefore, service water including a small number of colonies can beused for treatment of a patient, so that a cause of diseases can beremoved and the problem of infection in a clinic or hospital can be alsoprevented.

In the above-mentioned embodiment, one transponder 3 is attached to thewaterline 8 only. One transponder can prevent the biofilm of themicrobia from growing over the whole length of the waterline which isnot greater than 30 m. If the waterline has a length greater than 30 m,it is preferable that a plurality of transponders should be attached tothe waterline.

In the case where each of the waterlines 8 to 10 d is shorter than 30 m,the position of attaching the transponder is preferred to be near theend of the waterline as described above.

Although the transponder 3 is attached to the waterline 8 in theforegoing embodiment, the transponder 3 may be attached to any of thewaterlines 8, 9, 10, 10 a, 10 b, and 10 c for the dental unit 11. Forexample, the transponder 3 may be attached to any of a pipe line A ofthe waterline 9 to which the tap 20 as the end side of the waterline 8is connected, a pipe line B of the waterline 10 a near the outlet sideof the connection box 13, or a pipe line C of the waterline 10 b nearthe inlet side of the control center 15. It is also possible to attachthe transponders 3 to the plurality of positions and connect thetransponders 3 to the control unit 2 via the coaxial cables 4.

It is also possible to connect a plurality of transponders 3 to onecontrol unit 2 via the coaxial cables 4, and attach the transponders 3to waterlines of a plurality of dental units 11. With the configuration,in a dental clinic having a plurality of dental units, the apparatus ofthe present invention can be effectively used.

The present invention is carried out in the above-mentioned form and hasthe following effects.

(1) According to the apparatus and method of the present invention,growth of microbia in a waterline of a dental unit can be prevented byan audio electronic signal. The audio electronic signal is sent througha waterline so that an effect of prevention of the growth of themicrobia can be obtained within a wide range of the waterline connectedto the dental unit. Furthermore, a transponder can easily be attached tothe waterline.

(2) In particular, if an electric signal frequency-modulates around apredetermined frequency and the frequency modulation causes the audioelectronic signal to include a harmonics component, the effect of theprevention of the growth of the microbia can be made remarkable.

(3) If a face of the transponder which comes in contact with thewaterline has a concave shape whose section is circular, the transpondercan stably be attached to the waterline.

1. An apparatus for preventing growth of microbia propagating themselveson an internal wall of a waterline of a dental unit or for removing themicrobia, comprising: electric signal generating means for generating anelectric signal including an audio frequency component; a transponderincluding a coil and a case for housing the coil; and means forattaching the transponder to an external wall of the waterline, whereinthe electric signal is applied to the coil so that an audio electronicsignal to be sent through the waterline can be generated.
 2. Theapparatus according to claim 1, wherein the electric signalfrequency-modulates around a predetermined frequency.
 3. The apparatusaccording to claim 2, wherein the audio electronic signal includes aharmonics component by the frequency modulation.
 4. The apparatusaccording to claim 3, wherein the predetermined frequency is between1500 Hz and 2500 Hz.
 5. The apparatus according to claim 3, wherein aface of the transponder which comes in contact with the waterline has aconcave shape whose section is circular.
 6. The apparatus according toclaim 2, wherein the predetermined frequency is between 1500 Hz and 2500Hz.
 7. The apparatus according to claim 6, wherein a face of thetransponder which comes in contact with the waterline has a concaveshape whose section is circular.
 8. The apparatus according to claim 6,wherein the transponder is attached near an end of the waterline.
 9. Theapparatus according to claim 2, wherein a face of the transponder whichcomes in contact with the waterline has a concave shape whose section iscircular.
 10. The apparatus according to claim 1, wherein a face of thetransponder which comes in contact with the waterline has a concaveshape whose section is circular.
 11. The apparatus according to claim 1,wherein the transponder is attached near an end of the waterline. 12.The apparatus according to claim 2, wherein the transponder is attachednear an end of the waterline.
 13. A method for preventing growth ofmicrobia propagating themselves on an internal wall of a waterline of adental unit or for removing the microbia, comprising the steps of:generating an electric signal including an audio frequency component;attaching a transponder including a coil and a case for housing the coilto an external wall of the waterline; and applying the electric signalto the coil, thereby generating an audio electronic signal to be sentthrough the waterline.
 14. The method according to claim 13, wherein theelectric signal frequency-modulates around a predetermined frequency.15. The method according to claim 14, wherein the audio electronicsignal includes a harmonics component by the frequency modulation. 16.The method according to claim 14, wherein the predetermined frequency isbetween 1500 Hz and 2500 Hz.
 17. The method according to claim 16,wherein a face of the transponder which comes in contact with thewaterline has a concave shape whose section is circular.
 18. The methodaccording to claim 16, wherein the transponder is attached near an endof the waterline.
 19. The method according to claim 13, wherein a faceof the transponder which comes in contact with the waterline has aconcave shape whose section is circular.
 20. The method according toclaim 13, wherein the transponder is attached near an end of thewaterline.